TEM and DTA Study on the Stability of Al5Ti3- and h-Al2Ti-Superstructures in Aluminium-Rich TiAl Alloys
作者： Frank Stein , LC Zhang , Gerhard Sauthoff , Martin Palm
DOI: 10.1016/S1359-6454(01)00208-7
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摘要: Abstract The phases Al 5 Ti 3 and h-Al 2 Ti, which are superstructures of the L1 0 TiAl structure, frequently observed in as-cast low-temperature-annealed aluminium-rich alloys. strong decrease solubility aluminium with decreasing temperature leads to a supersaturation solid solution during cooling. decomposition supersaturated results precipitation superstructure at low temperatures. evolution resulting microstructures were studied as function time, temperature, composition by TEM DTA investigations on Ti–Al alloys 55 64 at.% Al. Both found not be equilibrium phases. is metastable below composition-dependent critical range about 750–900°C maximum value reached near stoichiometric composition. Above this rapidly dissolves. Extended lamellar +TiAl have been Ti–60 alloy after low-temperature annealing, whereas Ti–62 large single-phase domains grown. phase least up 1200°C. It slowly transforms into r-Al annealing.
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sci-hub.se 参考文章(11)
Oxidation of Intermetallics Wiley-VCH Verlag GmbH. ,(1997) , 10.1002/9783527612413
F. H. Froes, I. L. Caplan, Titanium '92 : science and technology Minerals, Metals & Materials Society, c1993. ,(1993)
I. Baker, E.P. George, R.D. Noebe, Interstitial and Substitutional Solute Effects in Intermetallics ,(1998)
Changhui Lei, Qiang Xu, Yong-Qian Sun, TEM investigation of interfaces between Ti3Al5 and TiAl2L Physica Status Solidi (a). ,vol. 179, pp. 77- 82 ,(2000) , 10.1002/1521-396X(200005)179:1<77::AID-PSSA77>3.0.CO;2-K
Q Feng, S.H Whang, Deformation of Ti–56 At.%Al single crystals oriented for single slip by 1/2<110] ordinary dislocations Acta Materialia. ,vol. 48, pp. 4307- 4321 ,(2000) , 10.1016/S1359-6454(00)00204-4
A. Loiseau, C. Vannuffel, TiAl2: A reentrant phase in the TiAl system Physica Status Solidi (a). ,vol. 107, pp. 655- 671 ,(1988) , 10.1002/PSSA.2211070221
T. Nakano, A. Negishi, K. Hayashi, Y. Umakoshi, Ordering process of Al5Ti3, h-Al2Ti and r-Al2Ti with f.c.c.-based long-period superstructures in rapidly solidified Al-rich TiAl alloys Acta Materialia. ,vol. 47, pp. 1091- 1104 ,(1999) , 10.1016/S1359-6454(99)00009-9
G Sattonnay, O Dimitrov, Long-range order relaxation and phase transformation in γ-TiAl alloys Acta Materialia. ,vol. 47, pp. 2077- 2088 ,(1999) , 10.1016/S1359-6454(99)00082-8
U.D. Kulkarni, Novel ordering transitions in off-stoichiometric γ-TiAl intermetallics and the similarities between these and the special point ordering processes in Ni-Mo alloys Acta Materialia. ,vol. 46, pp. 1193- 1207 ,(1998) , 10.1016/S1359-6454(97)00310-8
T Kawabata, T Kanai, O Izumi, Positive temperature dependence of the yield stress in TiAl L10 type superlattice intermetallic compound single crystals at 293–1273 K Acta Metallurgica. ,vol. 33, pp. 1355- 1366 ,(1985) , 10.1016/0001-6160(85)90245-7